The error occurs because your computer does not meet the minimum 3D hardware requirements to run the game. The minimum system requirements for BattleForge are:
- OS: Windows XP/Vista;
- Processor: 1.8GHz;
- RAM: 512MB;
- Hard Disk Space: 7GB;
- Video Card: 128MB Nvidia GeFirce 6/ATI Radeon 9500;
- DirectX 9.0c;
- DirectX 9.0c Compatible Sound Card;
- Resolution: 1024x768.
I suggest you try to configure the Hardware Acceleration in order to increase the performance supplied by your graphics hardware.